This is an interesting approach for a dot clock: use the SPI interface
to serially push pixels out, yielding 8 pixels per load and allowing
one to "unroll" the display update.
http://www.serasidis.gr/circuits/AVR_VGA/avr_vga.htm
Better yet, the following sites show that despite a small LCD display,
a machine resembling a glorified Speak'n'spell with a built-in BASIC
can be compelling for (at least the geekier elements of) the videogame
generations:
http://rasterweb.net/raster/computers/vtech.html
http://elevate.wordpress.com/2006/03/12/first-computer-program/
The company that made these is still around, and currently offers a
"vtech Genius Notebook"*, with a ~64x32 bitmap LCD, for $30. Looks
like they have devices with screens about half the resolution at $15.
BASIC no longer seems to be included, perhaps due to lack of demand (or
lack of desire to field the support calls?), but considering that they
also offer manufacturing services:
http://www.vtechcms.com/
they might be perfectly happy to build cheap programmable boxes if
someone else were willing to shoulder the market risk.
-Dave
*
http://www.vtechkids.com/product_page.cfm?productId=290?
tvFrom=&productImage=%5Ff%2F%5Fpw%2F%5Fthumb%2F64900%5Fthumb%2Ejpg&produ
ctStatus=a&tvFrom=&productId=290&productType=p&getProp=%5Btype+Function%
5D&loadImage=%5Btype+Function%5D&makeComingStripe=%5Btype+Function%5D&ma
keNewProductSnipe=%5Btype+Function%5D&theType=product
